Rotary compressor.



A. HUGUENIN. ROTARY COMPRESSOR.

APPLICATION FILED AUG.16,1909.

LSEQMW. Patented Aug. 27, 1912.

appertains to make and'use the same, refeven if made of brass or steel are too heavy.

ALBERT HUGUENIN, or ztTRIcH, SWITZERLAND ROTARY COMPRESSOR.

To all whom it may concern:

Be it known that I, ALBERT HUGUENIN, a citizen of the Republic of Switzerland, residing at Universitiitsstrasse 33, Zurich,

Switzerland, have invented certain new and erence being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

This invention relates to impellers for high speed rotary compressors. Cast wheels,

Riveted wheels have been proposed, but it has been found that the strains on them are u very heavy, as their resistance to vibration and oscillation is not sufficient.

This invention remedies the above-mentioned serious drawbacks.

It consists in making an impeller having sheet metal vanes fixed to 'a hub at their inner ends, this being the only point where they are held, ,while for the remaining and greater part of their length theyv are free. The vanes are of U or Z shape. width and thickness decreases toward their outer ends so that they are practically bodies of equal strength. Owing to this construction only the vanes produce any considerable centrifugal action, while the hub has a small circumferential velocity, and consequently the centrifugal forces produced are not considerable, so that it may be made strong enough to bear the centrifugal action of the vanes. The vanes themselves are stiffened by their U- or Z-shape in such manner that no loosening takes place, and

they are therefore specially adapted for working at very high circumferential speeds without any inconvenience, with the greatest safety and for long periods. As the compression capacity of a rotary wheel in creases with'the square of the circumferential speed,- such rotating Wheels can pro-- duce high pressure per stage. For a given total lncrease of pressure only a-few are re quired. The wheels themselves have the smallest possible weight, and as only a few of such light wheels have to'be mounted on one spindle for producing even a great increase of pressure, the spindle can be made with Specification of Letters Patent.

small loss by-l'eakage or "friction.

Their Patented Au 27,1912.

Application filed August 16, 1909. Serial No. 513,109.

a comparatively small diameter. This again enables stufling boxes and bearings with small bores to be used, which results in A machine provided with such rotating Wheels is therefore light inweight, has a small length and works 1n a highly economical manner.

The accompanying drawings show by way of example constructions according to this invention.

Figure 1 is a cross section, and Fig. 2 is an elevation of an impeller the vanes of which are on one side of the hub only. Fig. 3 is a section of an impeller having vanes on both sides of the hub. Figs. 4, 4? and 4 are side views of the vanes assembled 'and in diiferent positions. Fig. 5 is a section of an impeller having vanes on one side only and designed for, high velocities. Figs. 6 and 7 are perspective views of different forms of vanes.

The vanes a each consists of a web portion 2 and lateral flanges 3, said flanges being either directed toward the same side of the web to form a vane U-shaped in section, or directed toward opposite sides of the web 2 to form a vane Z-shaped insertion, as shown in Figs. 6 and 7. The flanges of the U-shaped vanes, Fig. 2, are continued forward at their bases, as indicated at 4, in the direction of rotation of the wheel, and to such an extent that they overlap the flanges of the preceding vanes and are riveted to the latter. In this way a very light and very efficient stiffening of the vanes with respect to each other is obtained at and adjacentto the elements to which they are secured, be it. a hub, as b or a ring,

as c.

Fig. 3 shows in cross section ail-impeller having inlets on bothsides. thereof are arranged in pairs, with their atljacent flanges against each other, the vanes being U-shaped in section. The adjacent flanges of each pair of vanes are held by a stiffened hub 2 and their outer flanges 3 are stiffened by rings 0. Each ring 0 has a channel on its outer periphery in which is wound a wire winding 03 that neutralizes or takes up the centrifugal forces of the stifl' ening rings 0 and the centrifugal forces of those portions of the vanes that transmit said forces to said rings. This winding 03 is preferably put on with an initial tension calculated to counteract the centrifugal forces on the ring so that the outer flanges The vanes a 8 of the vanes will not expand or be subjected to greater or less strains than the inner flanges when the impeller is working at full speed. The object of this is to avoid injurious bending strains on the vanes, one sided bending of the same, and an untrue rotation ofthe impeller. This point is to be more particularly considered with relation to impellers that have an inlet at one side only.

In Fig. at the vanes e are so assembled that their webs are not radial, but are inclined slightly forward in order that the lines through the resultant centers of gravity of the webs and flanges taken together and the axis of the impeller will be radial, in order to subject the vanes to tension lonly and not to bending; The vanes f Fig. 14 are shown as inclined backward for the purpose of guiding the air more efficiently.

The wire winding (2 ma be replaced by rings 9 Fig. 5.. These sti ening rings may be of drawn or wrought metal, and are either driven or shrunk into place. One ring g is secured on the hub portion b and is held in the state of rest of the impeller with an initial tension which produces a compres sion on the hub b and on the blades a toward the axis of rotation of the impeller which exceeds the centrifugal force tending to expand it when the impeller'is rotating atfull speed. The compression .is partly decreased whenlthe impeller assumesits full speed and the centrifugal action comes into operation. This tension does not relate to the ring 0 but to the ring g.

The flanges 3. of the U-shaped and Z shaped vanes may be diminished in width toward the periphery of the wheel, or may be dispensed with altogether at or near the periphery, or the U-shape may merge into crescent shape at the periphery. The main point is that the shape deviating from a plane must, to a considerable extent, be be yondthe securing rings, and thus the overhanging vanes considerably stifi'ened.

The invention consists essentially of an impeller having sheet metal vanes for high speed rotary compressors in which that part of the vanes which projects beyond the hub is U-shaped or Z-shaped in section; a modification in which the vanes are secured to a stiil'ening ring and to the hub Fig. 5; a modification in which the vanes are secured to the hub and are also secured to each other Fig. 2; a modification. in which the inner.

flanges of the vanes lie in the plane of the :=wheel and are secured to the hub and the outer flanges are secured to the stifi'ening rings Fig. 3. ,The stifi'ening ringor the hub can be stiifened by shrunk rings'or wire or bandwindings. j r

I claim- 1 An impeller for rotary compressors, comprising a hub, sheet iron vanes secured thereto, the vanes extending'freely beyond the outer circumference of the hub and having lateral strengthening flanges, the sectional area of the vanes decreasinggradually toward their outer ends, each vane being fixed to the hub with .onelateral flange and a supporting ring fixed to the other lateral flange, said supporting ring having no immediate connection with the compressor shaft.

2. An impeller for rotary compressors, comprising a hub, sheet iron vanes secured thereto, the vanes extending freely beyond the outer circumference of the hub and having lateral strengthening flanges, the crosssection of each vane being broken-line shaped, the sectional area of the vanes decreasing gradually toward their outer ends,

each vane being fixed to the hub with one lateral flange and a supportingring fixed to the other lateral'flange, said supporting ring having no immediate connection with the compressor shaft.

8.An impeller for rotary compressors,-

ing a. lateral strengthening flange on each edge and on the same side of the guiding-f face of each vane, the cross-section of each vane being broken-line shaped, the sectional area between the flanges and the guiding face ofcach vane dec'reasinggradually toward its outer end. i

In testimony that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

' ALBERT TIUGUENIN. VVitnessc's: I

ERNST Fiscnnn,

,Aur, Gunmen. 

